1. Field of the Invention
The present invention relates to a light source apparatus, and more particularly, relates to a light source apparatus for use in a projection apparatus.
2. Descriptions of the Related Art
Recent years, due to the advancement of technologies for manufacturing projection apparatuses, the light and compact projection apparatuses have become the mainstream product in the market. Driven by the ever-changing demand of the market, the projection apparatuses must be continuously improved in design and accordingly, the projection apparatus manufacturers must develop projection apparatuses with small profile, high efficiency and good image quality to meet the market demand.
Conventionally, projection apparatuses use ultra high performance (UHP) lamp as a light source. As LED technology make great progress, projection apparatuses have gradually begun to use LED instead of the UHP lamp as the light source. LEDs have many advantages such as long life, instant on and wide color gamut, etc. Therefore, efforts have been made in the art to employ LEDs as the light source. For example, a technology that employs a plurality of LEDs as the light source in a projection apparatus is disclosed in U.S. Patent Publication No. 2006/0023167. With this technology, a difficult method is required to collect light from the plurality of LEDs.
Other solution of the prior art uses single LED for one color of light source to simplify the structure of LED light source. For example, U.S. Patent Publication No. 2007/0195278 discloses a technology that employs three colors of single LED. However, this technology only applies to three-panel optical engine. For one-panel engine, light beams with three colors emitted by LED are required to combine and sent to a common integration rod. To overcome these drawbacks, various optical structures have been proposed in an attempt to improve the utilization efficiency of the light source and solve the congenital problem of LED light source causing the large divergent angle. However, optical structures currently available are rather complex in design, and the space required increases the size of the projection apparatus. On the other hand, efficient heat dissipation is needed because poor heat dissipation may cause an abrupt deterioration in the light emitting efficiency of the LEDs. Accordingly, as the sizes of projection apparatuses have decreased, and thus have less internal space, it is important to increase the heat dissipation efficiency of the light source.
In view of these problems confronted by miniaturized projection apparatuses, it is highly desirable in the art to provide a light source apparatus for use in a projection apparatus that has improved light source utilization efficiency, heat dissipation efficiency and a miniaturized profile.